This study seeks to learn the enzymatic, lipid, amino acid, electrophysiologic, psychophysical, and clinical characteristics of a variety of genetic retinal and choroidal disorders. The main attention will be directed toward the carriers of X-chromosomal-linked abnormalities, to the offspring of individuals with autosomal dominant disorders, and to the siblings of individuals with autosomal recessive disease. Attention will be directed to parents of individuals with autosomal recessive disease to learn if the heterozygote state can be recognized. The main conditions to be considered include Leber's amaurosis, retinitis pigmentosa, dominant optic atrophy, congenital night blindness, retinal cone dystrophy, and blue cone monochromism. Linkage studies will be carried out in an attempt to identify the gene locus of these disorders.